earlier for asus vivobook 15 k570ud i checked the asus website and i found that it supports m.2 sata iii. but when i checked the review at notebookcheck i found it different with PCIe x2 SK Hynix PC300 primary M.2 SSD.
here are the links:
https://www.asus.com/us/Laptops/K570UD/specifications/...